(a) Field of the Invention
The invention relates to a trolley, more particularly to a collapsible trolley.
(b) Description of the Prior Art
U.S. Pat. No. 4,917,392 discloses a collapsible luggage carrier including two wheeled carriages, each of which is provided with a substantially S-shaped cam slot. When a base member is rotated outwardly to its extended position, by means of the abutting action of the two cam slots, the two wheeled carriages can be rotated to the extended position in which they are parallel to each other. When the base member is rotates inwardly to its collapsed position, the two wheeled carriages can be rotated to a collapsed position.
In the above-described structure, the base member will abut against the edges of the cam slots when rotating between the extended and collapsed position and may damage the predetermined shape of the cam slots after a period of use so that the wheeled carriages cannot reach the predetermined extended or collapsed position. In a worse case, the structure of the wheeled carriages may be damaged. In addition, in view of the structural strength of the wheeled carriages, the size of the wheeled carriages must be above a certain size, and the size of the luggage carrier has to be above a certain size; therefore, it cannot meet the current trend for compact products.
The primary object of this invention is to provide a collapsible trolley that is extendable and collapsible by another driving mechanism.
In order to achieve the above-mentioned object, the collapsible trolley of the invention includes a main member; a carrier frame having one end pivotally provided on the main member so that the carrier frame is rotatable outwardly to an extension position or inwardly to a collapsed position; two wheel assembles, each of which includes a wheel frame and a wheel, the two wheel frames being pivotally provided on the main member so that the two wheel assemblies can be rotated outwardly to a use position, or inwardly to a collapsed position; and two first gears and two second gears, the two first gears being provided on the carrier frame, the two second gears being respectively provided on the wheel frames of the two wheel assemblies, and engaged with the two first gears. When the carrier frame is rotated to its extended position, it can bring the two wheel assemblies to rotate to their use position. When the carrier frame is rotated to its collapsed position, it can bring the two wheel assemblies to their collapsed position.